My guy has just been victimized (again) by vandalism of his construction equipment, in the form of sugar being poured into the gas tanks of a bulldozer and a couple of dump trucks. All of them would burn diesel fuel, I think.

What happens when sugar is added to diesel fuel? How does the engine act? What damage is caused? How soon does the damage show up?

Can't wait to see what you all do with this one. You've been very helpful in the past.

What's happening here is, it's November 13 and I'm still debating if I want to participate in the National Novel Writing Month's fast and dirty noveling event. In order to declare NaNo victory, I would have to write 50,000 words by midnight on the last day of November. I can't believe I'm still considering it, because that would mean I'd get very little else done in the next 2.5 weeks and have to put in some very long days. Regardless, I just now started this project, which may or may not become a NaNo novel. Either way this story has been banging around in my head for years, begging to be told, so I need to work on it whether I can finish a first draft in two weeks or not. We'll see, but the very first thing I find I need to research is sugar placed in gas tanks.

Sugar in diesel does nothing as it gets filtered in the strainers. In pure powder form, it will simply be blown out at the exhaust. Sugar in hydraulic fluid depends on where it is added. If there's a filter, it can strain the sugar out. Else it might fill in the clearance gap between piston and cylinder and scratch the cylinder's inner walls, leading to oil leakage and deterioration in the hydraulic systems load carrying capacity.

KU Researcher Adds A Dose Of Sugar To Diesel FuelLAWRENCE, Kans. -- A recipe for an alternative diesel fuel using agriculture resources found in Kansas begins with a liberal dose of something not normally used in engine fuels - sugar.

The primary goal of a University of Kansas researcher is to demonstrate technology that can convert grass, stalks, trash, farm byproducts, surplus grains and corn stover - corn stalks without the ears - into sugar for use as the primary component in fuel for diesel engines.

I was on a trip with a friend, and he pumped ten gallons of gas into my diesel truck. The mechanic figured he didn't want an explosion in his station, so he dropped the tank and drained it before we fired up the engine. I have no idea what would have happened, but better safe than sorry.

I'm more interested in the potential for explosions. Now there's an interesting angle! I have no qualms about killing someone off if the story needs it, and I could start this one off with a bang!

I know just the guy to ask for details about that, too. I have a friend who is a retired chemist who worked for one of the big oil companies. I bet he knows what happens if you mix diesel and gas and then hit the starter.

This is why I love posting here for preliminary research. Chances are, I wouldn't have been given that angle to contemplate without starting a discussion if I hadn't.

I'm going to write the opening both ways and then see what I can find during further research. The thing with NaNo is to get words down and figure out the details later, so I'm not going to delete a thing at this point. Later, when I do the second draft, I'll be cleaning all the mistakes up and expanding the story to 100,000 words or so, so plenty of time to make a decision later.

I bet he knows what happens if you mix diesel and gas and then hit the starter.

I think the blend has been changed over the years so that this is no longer necessary. But about 30 years ago, when diesel engines started finding their way into small passenger cars, it was a fairly common practice to add a small amount of gasoline to the fuel to prevent it from gelling at extremely cold temperatures.

So I doubt if there would be a catastrophic effect if larger amounts were added. It would probably explode, but that's what it's supposed to do (in the cylinder).

What happens when you use gasoline in a diesel engine? Either something expensive or something very expensive. Since gasoline is designed to be resistant to self-ignition, gasoline in a diesel engine either won't ignite or will ignite at the wrong time. Some diesel engines run leaner than gasoline engines (meaning that the air-fuel mix has a higher proportion of air than a gasoline engine). That increases the chances that the gasoline won't ignite and that unburnt fuel will be sent into the hot exhaust system--where, ironically, it could ignite, leading to possible exhaust damage. Even if you avoid that disaster, you can expect to pay $500 to drain the fuel tank, clean out the fuel lines, and refill the tank with diesel.

Some types of diesel engine use the diesel fuel as a lubricant for the fuel pump (remember, it's a fuel oil). It's said that running gasoline through such a pump could lead to serious damage or failure, turning a $500 repair into a $750-$1,250 one.

From the mythbusters link EvergreenThompson posted:

Quote

Bleach in the oil can destroy the engine. Confirmed The engine started but it soon started smoking, and very quickly overheated. The engine was so hot, that the undercarriage started burning and Adam fried an egg on the tailpipe. The engine was ultimately ruined.

Gas in a diesel system has the potential of destroying the fuel injectors.

Diesel injectors operate at very high pressure and what happens is with gas in a diesel system you will get pre-ignition in the fuel injectors which can lead to subsequent damaged to the injectors if one continues to try to keep the diesel engine running.

No big explosions likely to happen, plus in the construction equipment your bad guy would need hundreds of gallons of gasoline to displace enough diesel in the system to cause any real damage; just not very efficient.

If you want efficient devasting effects, destroy the electrical systems and slash all the tires, these are very costly and time consuming fixes.

Sugar in the tank: Not much is going to happen. Sugar is not soluble in either gasoline or diesel fuel. It may as well be dirt.

At worst, it *might* plug up the fuel filter... In a piece of construction equipment, the filter's going to be massive. In a car, there's a pre-filter on the fuel pump inlet in the tank, and a secondary fine filter in-line between the pump and the engine. Anything fine enough to make it through the sock on the pump inlet isn't going to hurt the pump, and anything that makes it past the fuel filter isn't going to hurt the injectors.

Now, that's for particulates... If we were talking about oh, say, another sugary-compound commonly found in an engine's cooling system.... Say, maybe, a couple gallons of antifreeze (ethylene glycol is nothing more than a complex sugar) and we all know what happens to sugar when we burn it... Carmel anyone? Antifreeze in the gas tank will turn to goo in the combustion chamber. I doubt it'll result in any sort of catastrophic failure (I've never tried it either), but it's bound to cause some issues.

Now, if it was diesel powered construction equipment, and the victim needs it to be vandalized.... Sugar in the tank isn't going to do squat. Slashing hydraulic hoses or punching holes in hydraulic tanks is going to cause much larger (and far more costly) headaches. If you're just looking for a simple vandalism for inconvenience's sake, pouring water in the fuel tanks will be the quickest way to go. Water sinks to the bottom, gets picked up by the inlet, and fills the fuel/water separator with nothing but water. It'll run for a couple of minutes, then just plain die. We all know water doesn't burn. I'm not sure what volume of water would be necessary, but it would kind of depend on the size of the tank and the location of the fuel pickup off the bottom. It won't cause any permanent damage, but will cause a major headache. Some of the newer systems in the more advanced equipment can detect the water level in the separator and shut down the engine before the water reaches the fuel rail, but it's no less of an inconvenience.

The most delicate and critical component of a diesel engine is the fuel pump. Sine diesel has to pump to extremely high pressure (~10,000 to 30,000 psi), the pump piston has very very small clearance and it use the diesel fuel as lubricant. Any trace of water, foreign fluid will ruin your pump.

Since sugar is not soluble in diesel, it will be just like dirt in fuel. Unless you have water in the tank, the sugar will dissolve into that water and eventually give you problem.

I say just disconnect the line and drain the tank.

Lucky you, if they pour some liquid such as brake fluid or alcohol in your tank, you would not have known it.

If we were talking about oh, say, another sugary-compound commonly found in an engine's cooling system.... Say, maybe, a couple gallons of antifreeze (ethylene glycol is nothing more than a complex sugar)

OK, this is off-topic, but this does remind me of a call to a local auto guru radio show (Paul Brand). The caller was winterizing his boat, and got a little bit mixed up as to which opening was which. He poured the RV antifreeze into the fuel tank.

Fortunately, he didn't run the engine. I think the only remedy was to drain the tank, and hope that the two liquids weren't soluble in each other. If they were mixed, I think you would have a lot of toxic waste on your hands.